fusee_cpp: rename source dir to fusee

fusee/program/source/fs/fusee_fs_storage.hpp

@@ -0,0 +1,145 @@
+/*
+ * Copyright (c) 2018-2020 Atmosphère-NX
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#pragma once
+#include <exosphere.hpp>
+#include "fusee_fs_api.hpp"
+
+namespace ams::fs {
+
+    class IStorage {
+        public:
+            virtual Result Read(s64 offset, void *buffer, size_t size) = 0;
+
+            virtual Result Write(s64 offset, const void *buffer, size_t size) = 0;
+
+            virtual Result Flush() = 0;
+
+            virtual Result SetSize(s64 size) = 0;
+
+            virtual Result GetSize(s64 *out) = 0;
+        public:
+            static inline bool CheckAccessRange(s64 offset, s64 size, s64 total_size) {
+                return offset >= 0 &&
+                       size >= 0 &&
+                       size <= total_size &&
+                       offset <= (total_size - size);
+            }
+
+            static inline bool CheckAccessRange(s64 offset, size_t size, s64 total_size) {
+                return CheckAccessRange(offset, static_cast<s64>(size), total_size);
+            }
+
+            static inline bool CheckOffsetAndSize(s64 offset, s64 size) {
+                return offset >= 0 &&
+                       size >= 0 &&
+                       offset <= (offset + size);
+            }
+
+            static inline bool CheckOffsetAndSize(s64 offset, size_t size) {
+                return CheckOffsetAndSize(offset, static_cast<s64>(size));
+            }
+    };
+
+    class ReadOnlyStorageAdapter : public IStorage {
+        private:
+            IStorage &m_storage;
+        public:
+            ReadOnlyStorageAdapter(IStorage &s) : m_storage(s) { /* ... */ }
+
+            virtual Result Read(s64 offset, void *buffer, size_t size) override {
+                return m_storage.Read(offset, buffer, size);
+            }
+
+            virtual Result Flush() override {
+                return m_storage.Flush();
+            }
+
+            virtual Result GetSize(s64 *out) override {
+                return m_storage.GetSize(out);
+            }
+
+            virtual Result Write(s64 offset, const void *buffer, size_t size) override {
+                return fs::ResultUnsupportedOperation();
+            }
+
+            virtual Result SetSize(s64 size) override {
+                return fs::ResultUnsupportedOperation();
+            }
+    };
+
+    class SubStorage : public IStorage {
+        private:
+            IStorage &m_storage;
+            s64 m_offset;
+            s64 m_size;
+        public:
+            SubStorage(IStorage &s, s64 o, s64 sz) : m_storage(s), m_offset(o), m_size(sz) { /* ... */ }
+
+            virtual Result Read(s64 offset, void *buffer, size_t size) override {
+                /* Succeed immediately on zero-sized operation. */
+                R_SUCCEED_IF(size == 0);
+
+                /* Validate arguments and read. */
+                R_UNLESS(buffer != nullptr,                                fs::ResultNullptrArgument());
+                R_UNLESS(IStorage::CheckAccessRange(offset, size, m_size), fs::ResultOutOfRange());
+                return m_storage.Read(m_offset + offset, buffer, size);
+            }
+
+            virtual Result Write(s64 offset, const void *buffer, size_t size) override{
+                /* Succeed immediately on zero-sized operation. */
+                R_SUCCEED_IF(size == 0);
+
+                /* Validate arguments and write. */
+                R_UNLESS(buffer != nullptr,                                fs::ResultNullptrArgument());
+                R_UNLESS(IStorage::CheckAccessRange(offset, size, m_size), fs::ResultOutOfRange());
+                return m_storage.Write(m_offset + offset, buffer, size);
+            }
+
+            virtual Result Flush() override {
+                return m_storage.Flush();
+            }
+
+            virtual Result GetSize(s64 *out) override {
+                *out = m_size;
+                return ResultSuccess();
+            }
+
+            virtual Result SetSize(s64 size) override {
+                return fs::ResultUnsupportedOperationInSubStorageA();
+            }
+    };
+
+    class FileHandleStorage : public IStorage {
+        private:
+            static constexpr s64 InvalidSize = -1;
+        private:
+            FileHandle m_handle;
+            s64 m_size;
+        public:
+            constexpr explicit FileHandleStorage(FileHandle handle) : m_handle(handle), m_size(InvalidSize) { /* ... */ }
+
+            ~FileHandleStorage() { fs::CloseFile(m_handle); }
+        protected:
+            Result UpdateSize();
+        public:
+            virtual Result Read(s64 offset, void *buffer, size_t size) override;
+            virtual Result Write(s64 offset, const void *buffer, size_t size) override;
+            virtual Result Flush() override;
+            virtual Result GetSize(s64 *out_size) override;
+            virtual Result SetSize(s64 size) override;
+    };
+
+}